Desktop App License Key Generator

A simple, secure command-line tool for generating RSA-signed license keys for desktop applications. This tool helps you create machine-specific licenses with customizable expiration dates.

What Does It Do?

This tool generates cryptographically signed license keys that:

• Are tied to a specific machine's MAC address
• Have a customizable validity period (in days)
• Use RSA signature verification to prevent tampering
• Can be validated offline by your desktop application

Features

• Secure: Uses RSA-2048 encryption with SHA-256 signatures
• Machine-Specific: License keys are bound to MAC addresses
• Offline Validation: No internet connection required for verification
• Easy to Use: Simple command-line interface
• Organized: Automatically saves keys with timestamps

How It Works

1. Key Generation (this tool):

   • Takes MAC address and validity period as input
   • Signs the data with a private key
   • Generates a Base64-encoded license key
   • Saves it to a timestamped file

2. Key Validation (your app):

   • Uses the included JavaScript validation code
   • Verifies the signature with the public key
   • Checks MAC address match
   • Tracks license expiration

Getting Started

Prerequisites

• Rust (1.70 or later)
• Cargo (comes with Rust)

Building from Source

# Clone the repository
git clone <your-repo-url>
cd license-key-generator

# Build the project
cargo build --release

# The executable will be in target/release/

Running the Generator

# On macOS/Linux
./target/release/desktop-app-license-key-generator

# On Windows
target\release\desktop-app-license-key-generator.exe

Usage

1. Run the application

2. Enter the MAC address of the target machine

   • Example: 00:1B:44:11:3A:B7

3. Enter the number of days the license should be valid

   • Example: 365 for one year

4. Enter a machine name (optional)

   • This is used for the filename
   • Press Enter to use the MAC address as the name

5. Get your license key

   • The key is displayed in the terminal
   • Automatically saved to License Keys/<name>_<timestamp>.txt

Example

Desktop App License Key Generator

Enter MAC ID:
00:1B:44:11:3A:B7

Enter number of days:
365

Enter machine name (optional, press Enter to use MAC ID):
John-Laptop

License key saved to file: License Keys/John-Laptop_20251205143022.txt
License Key: <base64-encoded-license-key>

Press Enter to exit...

Integrating with Your App

The js/main.js file contains a complete Node.js implementation for validating licenses in your application. Key functions:

• saveLicense(licenseKey) - Save and validate a new license
• validateLicense() - Check if the current license is valid
• getMacAddress() - Get the machine's MAC address

Quick Integration

const { validateLicense, saveLicense } = require('./main');

// When user enters a license key
try {
  saveLicense(userEnteredKey);
  console.log('License activated successfully!');
} catch (error) {
  console.log('Invalid license key');
}

// Check license on app startup
if (validateLicense()) {
  // License is valid, start app
} else {
  // License invalid or expired, show activation screen
}

Security Notes

⚠️ Important: The private key in this repository is for demonstration purposes. For production use:

1. Generate your own RSA key pair:

   # Generate private key
   openssl genrsa -out private_key.pem 2048
   
   # Extract public key
   openssl rsa -in private_key.pem -pubout -out public_key.pem

2. Update the keys:

   • Replace the private_key_pem in src/main.rs
   • Replace the PUBLIC_KEY in js/main.js

3. Keep your private key secure:

   • Never share it publicly
   • Store it in a secure location
   • Consider using environment variables or secure vaults

File Structure

license-key-generator/
├── src/
│   └── main.rs          # Key generator (Rust)
├── js/
│   └── main.js          # License validator (Node.js)
├── assets/
│   └── icon.ico         # Application icon
├── License Keys/        # Generated keys saved here
├── Cargo.toml          # Rust dependencies
└── README.md           # You are here

License Format

License keys are Base64-encoded and contain:

• RSA signature of the MAC+days payload
• Validity period (in days)

Format: <signature>__<days>__

Contributing

Contributions are welcome! Feel free to:

• Report bugs
• Suggest features
• Submit pull requests

License

This project is available as-is for personal and commercial use. Feel free to modify and adapt it to your needs.

Questions?

If you have questions or run into issues, please open an issue on GitHub.

---

Made with ❤️ for developers who need simple, secure licensing for their desktop apps.